You've probably heard a lot of people tell you to "stay positive," but being overly optimistic isn't always the best way to achieve your goals. The Wall Street Journal explains that it can actually cause anxiety.

While optimism can keep you motivated, it can also make failure seem a lot scarier, stopping you in your tracks:

Just thinking in sober detail about worst-case scenarios—a technique the Stoics called "the premeditation of evils"—can help to sap the future of its anxiety-producing power. The psychologist Julie Norem estimates that about one-third of Americans instinctively use this strategy, which she terms "defensive pessimism." Positive thinking, by contrast, is the effort to convince yourself that things will turn out fine, which can reinforce the belief that it would be absolutely terrible if they didn't.

Obviously, you'd want to avoid overdoing this though. If you get too negative, you might just create overly easy or realistic goals, or just giving up before you start. A bit of negative thinking, however, can reduce that anxiety and help you realize that failing isn't so bad. Hit the link to read more.